Prevent/detect usb flash cloning/restoring

Hi there,

I have an issue regarding developing a secure way of doing licensing for a software application. This application would allow the user the possibility to use some how of "offline licenses" for consuming, stored in an encrypted file.
The problem is that the main vulnerability is when the user decides to hack the licensing system, by cloning at first the entire usb flash contents (cloning byte by byte) and after consuming all of it's x licenses, he would restore the clone to the same usb stick and re-consume the same licenses.

So, the question to you would be:
Is there a way to somehow know if a usb flash has been cloned ? Maybe with some sort of specific generic usb flash hardware feature including some counters or something like that?
Or do you have another idea on doing the "offline licenses" mechanism safe (without requiring internet connection and server sync) ?

Thank you !

Tags: Flash, Hardware, Security, USB, Clone